People with COVID-19 may be at higher risk for rare, vision-threatening eye conditions, according to a new study. Photo by SofieZborilova/Pixabay
April 14 (UPI) -- The risk for potentially vision-threatening eye conditions among adults is up to 50% higher in the six months after COVID-19 infection than it is in those who avoid the virus, a study published Thursday found.
However, these eye-related complications, which include clots in the main artery supplying blood to the eyes or similar blockages in the veins that drain blood from the retina, still are "rare," the researchers said in an article published Thursday by JAMA Ophthalmology.
Among more than 432,000 patients with confirmed COVID-19 infection included in the study, 16 developed retinal artery occlusion, a blockage in the main artery supply blood to the eye, the data showed.
In addition, 65 developed a retinal vein occlusion, or a blockage in one of the veins that drains blood from the eyes, within six months of infection, according to the researchers.
Although both complications are rare, a person's risk for developing a retinal vein occlusion is 54% higher in the six months following COVID-19 infection than in the six months before they contract the virus, the researchers said.
For retinal artery occlusion, the risk is 35% greater after infection, they said.
"We found that the incidence of retinal vein occlusions increased in the six months after COVID-19 infection, even after controlling for other risk factors," study co-author Dr. Bobeck Modjtahedi told UPI in an email.
"Retinal vein occlusions are a serious eye condition that can result in permanent vision loss, but some of the complications of this condition, such as swelling in the retina, can be managed," said Modjtahedi, vitreoretinal surgeon at Kaiser Permanente in Southern California.
"For that reason, it is important for patients who experience changes to their vision or eye symptoms after COVID-19 to seek care," added Modjtahedi, who also is an associate professor at the Kaiser Permanente Bernard J. Tyson School of Medicine in Pasadena, Calif.
Retinal vein occlusion is a blockage of the small veins that carry blood away from the retina, the layer of tissue at the back of the inner eye that converts light images to nerve signals and sends them to the brain, according to the National Library of Medicine.
It is most often caused by hardening of the arteries and the formation of a blood clot and it, in turn, can lead to vision-threatening conditions such as glaucoma and macular edema, or the leakage of fluid into the record, it says.
With retinal artery occlusion, a branch of the retinal artery is blocked, meaning a portion of the retina will not receive sufficient blood and oxygen, causing vision loss.
Both conditions are typically associated with diabetes, heart disease and high blood pressure, though COVID-19 has also been linked with the development of blood clots in earlier studies.
In this study, patients who developed retinal vein occlusion typically did so six to eight weeks after testing positive for the virus, while most of those who experienced retinal artery occlusion had it within 10 to 12 weeks of COVID-19 diagnosis, the data showed.
"If a patient notices a change in their vision, it is important to be evaluated as soon as possible," Modjtahedi said.
"Patients should try maximize their general health, controlling their blood pressure, doing a good job with their blood sugars, if diabetic, and controlling their cholesterol levels [as] these are things that can reduce the risk of retinal vein occlusion in general," he said.